1. Field of the Invention
The present disclosure relates to sleeves, gown assemblies, such as those used in clean rooms, hospitals, and the like, gown and cuff assemblies, and gown and air shower assemblies.
2. Description of the Related Art
Clean rooms and other sensitive environments have very strict requirements for operation intended to minimize contamination, either of product within the environment, or contamination of personnel or articles which, at some point, would exit the restricted environment. For clean rooms, procedures and restrictions attempt to minimize the possibility of contamination of product being made in the clean room caused by particulates or charged particles brought into the clean room from the outside. In medical applications, such as surgery suites, procedures and restrictions seek to minimize the possibility of infection or other contamination of a patient by organisms brought in from the outside by operating room personnel. In research facilities, as another example, restrictions and procedures are in place to minimize the possibility organisms or contaminants escape the facility either carried by personnel or on garments or equipment used within the facility. In many such situations, personnel are required to wear protective clothing including gowns, headwear, footwear, gloves and often masks. This apparel serves to minimize the undesirable contamination or exposure.
For illustrative purposes only, the following discussion will be directed primarily to clean room environments, such as those for manufacturing semiconductor devices. Clean rooms are generally well controlled environments made up of sealed or otherwise contained rooms with positive pressure ventilation and environmental regulation often producing no more than one hundred parts per million of environmental particulates.
Personnel working in clean room environments typically are required to wear full body gowns, headwear, footwear and gloves, such as latex or rubber gloves such as those worn for surgery and medical examinations. Face masks are also typically required, or the full body gowns may include a face cover. Partial gowns such as labcoats may also be used, such as with a laminar flow hood, in which case only a partial body covering is used. Partial gowns might include only a torso cover with sleeves and a neck and possibly a head cover. Gloves would typically be worn with a partial gown as well.
After putting on this apparel, personnel may enter an air shower to eliminate as much as possible any airborne contaminants or contaminants carried on the person's clothing or protective apparel. The air shower is a positive pressure ventilated room including a number of higher pressure air jets directing forced air streams at the center of the room where the person would be standing. The air jets are intended to push off any particulates from the garments or apparel, after which the airborne particulates are removed from the air shower by the ventilation system. While the air shower is capable of removing some particulates in this manner, not all particulates which may eventually become airborne and contaminate a work piece in the clean room can be removed in the air shower. For example, the air streams from the pressurized air supply sometimes force particulates into the fabric of the garment rather than sweeping it off the garment. Additionally, folds created in the garment after the garment has been put on often retain particulates which are difficult to remove through an air shower. Low velocities are effective, if at all, in removing only large particles from the gown. High velocity air showers are more effective in removing both large and small particles, but some small particles can actually be driven into the fabric weave. The embedded particles may later become disengaged from the garment inside the clean room.
Within the clean room area, there may be certain areas where personnel are required to exercise extra care to eliminate as much as possible the contamination of an area or of a work piece. For example, extra care is taken near a wet bench area, where sensitive or critical processes of the work pieces are handled. In this area, a positive air pressure is typically provided to further remove particulates from the wet bench area, thus creating a region within the clean room that preferably has a lower particle count. However, personnel moving between the wet bench area and other areas in the clean room may carry particulates embedded in their gowns to the wet bench area, consequently increasing the likelihood of contaminating the work piece they are working on.
The sleeves are of particular importance because the sleeves are the garment areas closest to and most likely come into contact with any work pieces as the personnel work in between the wet bench area and the rest of the clean room. Thus, personnel may change into another gown and go through another air shower before working near the wet bench, which is inconvenient and adds time and money to the manufacturing process.
Current gowns use breathable fabrics or non-breathable fabrics or materials. Non-breathable materials include TYVEK, vinyl and other common materials. Breathable fabrics include Goretex and polyester and polyester blend fabrics and other woven or non-woven materials. The breathable materials or fabrics allow moisture to escape from the operator through the fabric for comfort, and particles larger than 0.3 microns are also filtered or blocked, and not allowed to escape from the gown. Seams and joints are folded and double stitched to prevent holes from which particles can escape.
With such gowns, one source of highest probability of contamination is the sleeve and hand area for the garment and operator. Where rubber or latex gloves are used by the operator, the glove cuff is typically placed over the end of the sleeve, and is held in place by the elasticity of the cuff on the glove. However, cuff roll down often occurs, and the seal between the glove and the wrist area of the garment may be jeopardized. Some glove designs have extra long cuffs or integral elastic bands around the cuff to enhance sealing. These gloves are relatively uncomfortable, and cause buildup of heat and perspiration inside the glove and along the cuff. Airflow is restricted and moisture is trapped within the glove and in the wrist area.
The integrity of the hand and wrist area of the operator is of utmost importance since it is that area which is closest to and most likely comes into contact with any work pieces that the operator is handling. Therefore, extra measures are warranted to ensure that any contamination from the hands and wrist areas of the operator and the operator's garments are minimized. Since humans are a major source of contamination in clean room environments, some extra measures should be directed to minimizing contamination from human sources. Gown design is very important to reduce contamination from the body through the gown, but 100% particle containment would require a gown that was uncomfortable to wear and one which would most likely preclude efficient and effective work. The present source of highest contamination from the body and from the gown is the glove and gown interface. No adequate seal is presently achieved with current techniques.
Longer glove cuff lengths add cost to the glove and promote allergic reaction due to inadequate ventilation. Inadequate ventilation, heat and moisture buildup results especially around the palm of the operator's hand and between the fingers. Any allergic reaction is accentuated for those who react to latex or wearing rubber gloves because of the inadequate ventilation. Longer cuff lengths, nonetheless, are not completely secure.
Glove seals formed by an elastic band used in conjunction with the glove cuff increases the cost of the glove, requires an extra operation and also is not completely secure.
Tape seals used to seal the glove around the sleeve cuff secures twisted or folded portions of the cuff and removes slack from the cuff, but requires an extra operation, and is itself not completely secure. The glove can still slide off of or move relative to the sleeve cuff, such as when the sleeves are pulled during normal arm movement or otherwise.
In such circumstances, any seal between the glove and the sleeve cuff may be broken or changed. Additionally, taping the sleeve cuff and the glove cuff together is suitable only for disposable gowns, since the tape typically leaves a residue on the garment, which is undesirable for reusable garments.
There exists, therefore, a need for an improved apparatus and method for removing possible particulates and other contaminants from operator's gowns, as well as an improved apparatus and method for using the gowns and for creating an improved glove to gown seal.